Pump spraying gap flow eliminating device based on rotor embedded ring design

Abstract

The invention relates to a pump-jet clearance flow eliminating device based on rotor embedded ring design, and relates to the field of ship vibration noise technical equipment, the pump-jet clearance flow eliminating device comprises a pump-jet propeller guide pipe, and the interior of the pump-jet propeller guide pipe is coaxially and rotatably connected with a pump-jet propeller rotor; a rotor blade tip lantern ring is coaxially and fixedly connected to the outer side of the pump-jet propeller rotor, the inner diameter of the rotor blade tip lantern ring is larger than that of the pump-jet propeller guide pipe, and a guide pipe inner ring cavity is formed in the position, opposite to the rotor blade tip lantern ring, of the inner side wall of the pump-jet propeller guide pipe. The rotor blade tip lantern ring is located in the guide pipe inner ring cavity. According to the invention, pump jet propeller flow-induced vibration and gap cavitation noise caused by gap flow can be eliminated.

Description

Technical Field

[0001] The present application relates to the field of ship vibration and noise technical equipment, and in particular to a pump jet gap flow elimination device based on a rotor embedded ring design. Background Art

[0002] The pump-jet propulsion system is a combined propulsion device with high propulsion efficiency, good operating performance and low noise level, which is composed of an annular duct, a stator and a rotor. Due to the requirements of the "International Ship Noise Control Regulations" and the "Guidelines for Reducing Underwater Noise from Commercial Ships" promulgated by the International Maritime Organization (IMO), ships should not cause excessive noise pollution to the surrounding environment when sailing, and the pump-jet propulsion system has outstanding advantages in reducing noise, and its application value in this aspect is huge, which also puts forward a great demand for the research and development of pump-jet propulsion system, especially the research on the noise of pump-jet propulsion system.

[0003] There is a gap between the rotor blade tip and the inner wall of the duct of a pump-jet propulsor. When the flow field flows through the blade tip gap, vortices and leakage flows will be formed at the blade tip gap due to the relative movement of the blade tip and the duct wall and the pressure difference between the thrust surface and the thrust surface of the rotor. On the one hand, the complex vortex will induce vortex-induced vibration and gap cavitation. On the other hand, the large pressure pulsation will also aggravate the vibration of the duct and rotor and transmit it to the hull, causing strong stern coupled vibration noise, which affects the acoustic performance of the ship in many ways. Summary of the invention

[0004] In order to eliminate flow-induced vibration and gap cavitation noise of a pump-jet propulsor caused by gap flow, the present application provides a pump-jet gap flow elimination device based on a rotor embedded ring design.

[0005] The present application provides a pump jet gap flow elimination device based on a rotor embedded ring design, which adopts the following technical solution:

[0006] A pump-jet gap flow elimination device based on a rotor embedded ring design includes a pump-jet propeller duct, the interior of the pump-jet propeller duct is coaxially rotatably connected to a pump-jet propeller rotor, the outer side of the pump-jet propeller rotor is coaxially fixedly connected to a rotor blade tip ring, the inner diameter of the rotor blade tip ring is larger than the inner diameter of the pump-jet propeller duct, an inner duct inner ring cavity is opened at the inner side wall of the pump-jet propeller duct at a position relative to the rotor blade tip ring, and the rotor blade tip ring is located in the duct inner ring cavity.

[0007] Optionally, the diameter of the inner annular cavity of the duct is larger than the outer diameter of the rotor blade tip ring.

[0008] Optionally, a damping layer is provided on the side wall of the pump-jet propulsor duct relative to the inner annular cavity of the duct, and a distance is left between the damping layer and the outer side wall of the rotor blade tip ring.

[0009] Optionally, the inner diameter of the inner annular cavity of the catheter is the same as the inner diameter of the rotor blade tip ring.

[0010] Optionally, empty annular cavities are respectively opened on both sides of the inner annular cavity of the catheter, and the empty annular cavities are connected with the inner annular cavity of the catheter, and the connecting line of the two empty annular cavities is arranged along the axial direction of the pump-jet propulsor catheter.

[0011] Optionally, the length of the rotor blade tip ring along the axis of the pump-jet propulsor duct is greater than the length of the pump-jet propulsor rotor and the rotor blade tip ring at the connection position along the axis of the pump-jet propulsor duct.

[0012] Optionally, the pump-jet propulsor rotor includes a central rotating shaft, an outer side wall of the central rotating shaft is fixedly connected to rotor blades, a plurality of rotor blades are circumferentially arranged along the outer side wall of the central rotating shaft, and the outer sides of the plurality of rotor blades are fixedly connected to the inner side wall of the rotor blade tip ring.

[0013] Optionally, a pump-jet propeller stator is disposed inside the pump-jet propeller duct, and the pump-jet propeller stator and the pump-jet propeller rotor are coaxially disposed.

[0014] In summary, the present application includes at least one of the following beneficial technical effects:

[0015] 1. The flow field pulsation characteristics at the gap of the traditional pump-jet propulsor blade tip, the pulsating pressure at the gap increases sharply. By modifying the rotor blade tip and the inner wall of the duct at the gap of the traditional pump-jet propulsor, the blade tip is equipped with a collar structure and embedded in the ring cavity structure of the inner wall of the duct, and the pressure pulsation peak at the original gap measurement point is eliminated. This solution effectively eliminates the gap flow field pulsation and gap leakage flow by modifying the gap structure, and has no effect on the propulsion efficiency, thereby greatly reducing the rotor blade tip gap cavitation and propeller vibration noise caused by the gap flow, and effectively improving the acoustic performance of the pump-jet propulsor. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of a pump jet gap flow elimination device based on a rotor embedded ring design in an embodiment of the present application.

[0017] Figure 2 It is a cross-sectional view of a pump jet gap flow elimination device based on a rotor embedded ring design in an embodiment of the present application.

[0018] Figure 3 It is a schematic structural diagram of a rotor blade tip ring of a pump jet gap flow elimination device based on a rotor embedded ring design in an embodiment of the present application.

[0019] Explanation of the reference numerals: 1. pump-jet propeller duct; 11. inner annular cavity of the duct; 12. empty annular cavity; 2. pump-jet propeller stator; 3. pump-jet propeller rotor; 31. central rotating shaft; 32. rotor blades; 4. rotor blade tip ring. DETAILED DESCRIPTION

[0020] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0021] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0022] The following is combined with Figure 1-3 This application is described in further detail.

[0023] The present application embodiment discloses a pump jet gap flow elimination device based on a rotor embedded ring design. Figure 1 , Figure 2 A pump-jet gap flow elimination device based on a rotor embedded ring design includes a pump-jet propeller duct 1, which is a ring-shaped structure, and a pump-jet propeller stator 2 is arranged inside the pump-jet propeller duct 1, and a pump-jet propeller rotor 3 is also arranged on one side of the pump-jet propeller stator 2, the pump-jet propeller rotor 3 is rotatably connected to the pump-jet propeller duct 1, and the pump-jet propeller rotor 3 is coaxially arranged with the pump-jet propeller duct 1.

[0024] The pump-jet propeller rotor 3 includes a central rotating shaft 31, which is coaxially arranged with the pump-jet propeller duct 1. Rotor blades 32 are fixedly connected to the outer side of the central rotating shaft 31, and a plurality of rotor blades 32 are equidistantly arranged along the side wall of the central rotating shaft 31.

[0025] Reference Figure 2 , Figure 3 A rotor blade tip ring 4 is coaxially arranged on the outer side of the pump-jet propulsor rotor 3. The rotor blade tip ring 4 is an annular structure, and the inner side wall of the rotor blade tip ring 4 is fixedly connected to the outer side walls of all the rotor blades 32.

[0026] The inner wall of the pump-jet thruster duct 1 is provided with a duct inner annular cavity 11 at a position relative to the rotor blade tip collar 4, and the interior of the duct inner annular cavity 11 is relatively connected to the interior of the pump-jet thruster duct 1. The rotor blade tip collar 4 extends into the interior of the duct inner annular cavity 11, and the diameter of the duct inner annular cavity 11 is greater than the diameter of the outer wall of the rotor blade tip collar 4, so that a gap is left between the position of the pump-jet thruster duct 1 relative to the outer wall of the duct inner annular cavity 11 and the outer wall of the rotor blade tip collar 4.

[0027] The damping paint is applied to the outer wall of the pump-jet thruster duct 1 relative to the inner annular cavity 11 of the duct, and a distance is left between the damping paint and the outer wall of the rotor blade tip collar 4. By applying the damping paint, it can be ensured that the rotor blade tip collar 4 and the pump-jet thruster duct 1 will not collide with the inner annular cavity 11 of the duct when the deformation and vibration amplitude of the rotor blade 32 are not greater than 9% of the diameter.

[0028] The inner wall diameter of the rotor blade tip collar 4 is the same as the inner wall diameter of the pump-jet propeller duct 1 .

[0029] The inner wall of the pump-jet thruster duct 1 is provided with empty annular cavities 12 on both sides along the axis direction of the pump-jet thruster duct 1 relative to the inner annular cavity 11 of the duct, and the empty annular cavity 12 is relatively connected with the inside of the inner annular cavity 11 of the duct. A side wall of the empty annular cavity 12 facing away from the rotor blade tip collar 4 is spaced from the outer side wall of the rotor blade tip collar 4.

[0030] The length of the rotor blade tip collar 4 along the axial direction of the pump-jet propeller duct 1 is greater than the length of the relative connection between the rotor blade 32 and the rotor blade tip collar 4 along the axial direction of the pump-jet propeller duct 1.

[0031] There is a gap between the blade tip of the traditional pump-jet propulsor rotor and the inner wall of the duct. When the flow field flows through the gap between the blade tips, vortices and leakage flows are formed. On the one hand, complex vortices will induce vortex-induced vibration and gap cavitation. On the other hand, large pressure pulsations will also aggravate the vibration of the duct and rotor and transmit them to the hull, causing strong stern coupled vibration noise, which affects the acoustic performance of the ship in many ways.

[0032] The rotor embedded ring design method adds a ring structure to the tip of the rotor blade 32 and embeds the ring structure into the annular cavity structure of the inner wall of the duct at the gap, so that the pump-jet structure completely eliminates the gap structure, thereby suppressing the vortex-induced vibration and gap cavitation caused by the gap flow, and reducing the vibration noise of the propeller; at the same time, comparing the propulsion efficiency of the rotor embedded ring design pump-jet propeller and the parent type pump-jet propeller, there is no obvious difference between the two, that is, the design does not affect the hydrodynamic performance.

[0033] In some embodiments, a pump-jet propulsion scale model is taken as an example, wherein the pump-jet propulsion duct 1 in the pump-jet scale model is 0.177m long, the pump-jet propulsion rotor 3 is 0.222m in diameter, the pump-jet propulsion rotor 3 has 10 blades, and the pump-jet propulsion stator 2 has 13 blades. The rotor blade 32 tip collar is 90mm long in the axial direction (the blade tip is 50mm long in the axial direction), and the front and rear are extended by 20mm relative to the front and rear of the blade tip, and the rotor blade 32 tip collar is 2.5mm thick; the inner ring cavity 11 structure of the duct at the gap is 134mm long in the axial direction (including the damping layer), and the front and rear are extended by 22.5mm relative to the rotor blade 32 tip collar, the cavity thickness is 19mm (including the damping layer), and the damping coating is coated inside, and the damping coating thickness is 2mm.

[0034] In actual operation, since the ring structure of the rotor blade 32 is wider than the opening of the ring cavity 11 in the duct, the opening of the ring cavity is completely covered by the ring structure of the rotor blade 32, eliminating the gap structure and the hole cavity structure, so that the fluid can only flow downstream through the blade; at the same time, the cumulative value of the deformation and vibration amplitude of the rotor blade 32 under normal working conditions is less than 9% of the blade diameter, and the reserved cavity can ensure that the ring and the ring cavity do not collide. Thus, a better vibration reduction and noise reduction effect is achieved without any negative effects such as structural impact and reduced propulsion efficiency.

[0035] In this application, the term "plurality" means at least two or more than two, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0036] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

Claims

1. A pump jet gap flow elimination device based on a rotor embedded ring design, characterized in that: The invention comprises a pump-jet propeller duct (1), wherein the pump-jet propeller duct (1) is coaxially rotatably connected to a pump-jet propeller rotor (3), and the outer side of the pump-jet propeller rotor (3) is coaxially fixedly connected to a rotor blade tip ring (4), wherein the inner diameter of the rotor blade tip ring (4) is larger than the inner diameter of the pump-jet propeller duct (1), and an inner duct inner ring cavity (11) is formed on the inner side wall of the pump-jet propeller duct (1) at a position relative to the rotor blade tip ring (4), and the rotor blade tip ring (4) is located in the inner duct inner ring cavity (11).

2. The pump jet gap flow elimination device based on the rotor embedded ring design according to claim 1 is characterized in that: The diameter of the inner annular cavity (11) of the duct is greater than the outer diameter of the rotor blade tip collar (4).

3. The pump jet gap flow elimination device based on the rotor embedded ring design according to claim 2 is characterized in that: The pump-jet propeller duct (1) is provided with a damping layer on the side wall relative to the inner annular cavity (11) of the duct, and a distance is left between the damping layer and the outer side wall of the rotor blade tip collar (4).

4. The pump jet gap flow elimination device based on the rotor embedded ring design according to claim 2 is characterized in that: The inner diameter of the inner annular cavity (11) of the duct is the same as the inner diameter of the rotor blade tip collar (4).

5. The pump jet gap flow elimination device based on the rotor embedded ring design according to claim 1 is characterized in that: Empty annular cavities (12) are respectively provided on both sides of the inner annular cavity (11) of the catheter, and the empty annular cavity (12) is communicated with the inner annular cavity (11) of the catheter, and the connecting line of the two empty annular cavities (12) is arranged along the axial direction of the pump-jet propulsor catheter (1).

6. The pump jet gap flow elimination device based on the rotor embedded ring design according to claim 1 is characterized by: The length of the rotor blade tip collar (4) along the axis of the pump-jet propeller duct (1) is greater than the length of the pump-jet propeller rotor (3) and the rotor blade tip collar (4) at the connection position along the axis of the pump-jet propeller duct (1).

7. The pump jet gap flow elimination device based on the rotor embedded ring design according to claim 1 is characterized by: The pump-jet propeller rotor (3) comprises a central rotating shaft (31), the outer side wall of the central rotating shaft (31) being fixedly connected with a rotor blade (32), a plurality of the rotor blades (32) being circumferentially arranged along the outer side wall of the central rotating shaft (31), and the outer sides of the plurality of rotor blades (32) being fixedly connected to the inner side wall of the rotor blade tip ring (4).

8. The pump jet gap flow elimination device based on the rotor embedded ring design according to claim 1 is characterized by: A pump-jet propeller stator (2) is arranged inside the pump-jet propeller duct (1), and the pump-jet propeller stator (2) and the pump-jet propeller rotor (3) are coaxially arranged.

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